PROPOSAL: Make Applicative a superclass of Monad
ajb at spamcop.net
ajb at spamcop.net
Tue Jun 24 19:51:40 EDT 2008
G'day all.
Quoting Isaac Dupree <isaacdupree at charter.net>:
> Is there any practical way we can make this change while still making
> it possible to compile Haskell98 programs at all?
This is being redirected to haskell-prime, of course, however, while we're
on the topic, it needs to be said yet again:
It's a severe pain to make class hierarchies more granular if you have
to declare an instance for all of them. I support the principle of
making Applicative a superclass of Monad. However, I don't want to
have to declare an instance for Functor and Applicative just to declare
an instance for Monad.
There are obvious defaults, and I should be able to get them with no
effort, or at the very least, no more effort than a "deriving"-like
annotation.
Cheers,
Andrew Bromage
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